GEO-HEAT CENTER Quarterly Bulletin

- Oregon and California - Direct-Use In Action

GEO-HEAT CENTER Quarterly Bulletin

Vol. 20, No. 1 MARCH 1999

ISSN 0276-1084

OREGON INSTITUTE OF TECHNOLOGY -KLAMATH FALLS, OREGON 97601-8801 PHONE NO. (541) 885-1750

Vol. 20, No. 1 March 1999

GEO-HEAT CENTER QUARTERLY BULLETIN

ISSN 0276-1084

A Quarterly Progress and Development Report on the Direct Utilization of Geothermal Resources

CONTENTS

Aquaculture in the Imperial Valley – A Geothermal Success Story - Kevin Rafferty

Klamath Falls Geothermal District Heating Systems

Brian Brown

The Oregon Institute of Technology Geothermal Heating System – Then and Now

Tonya L. Boyd

Reconstruction of a Pavement Geothermal Deicing System John W. Lund

Love Three Hot Springs out of the Thousands – Hot Creek, Fields and Ash

Bill Kaysing

The Geo-Heat Center Website Tonya “Toni” Boyd

In Memory of Dr. Tibor Boldizar (1913-1998)

International Geothermal Days – Oregon 1999

Geothermal Pipeline

Progress and Development Update Geothermal Progress Monitor

Cover Photos (left to right, top to bottm): Tilapia being loaded fro shipment at California Desert Fish Farm, Imperial Valley, CA; New Klamath County Government Center building with sidewalk snow melting system; Oregon Institute of Technology stair snow melting system;

and Klamath Falls highway snow melting system installation (ODOT).

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PUBLISHED BY

GEO-HEAT CENTER Oregon Institute of Technology

3201 Campus Drive Klamath Falls, OR 97601

Phone: 541-885-1750 Email: [email protected]

All articles for the Bulletin are solicited. If you wish to contribute a paper, please contact the editor at the above address.

EDITOR

John W. Lund

Typesetting/Layout – Donna Gibson Graphics – Tonya “Toni” Boyd

WEBSITE

FUNDING

The Bulletin is provided compliments of the Geo- Heat Center. This material was prepared with the support of the U.S. Department of Energy (DOE Grant No. DE-FG07-90ID13040). However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors(s) and do not necessarily reflect the view of USDOE.

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Kevin Rafferty Geo-Heat Center INTRODUCTION

The Salton Sea and Imperial Valley area of southern California has long been recognized as a “hot spot” of geo- thermal development. In the geothermal industry, this area has for some time been synonymous with electric power gen- eration projects. Starting with the first plant in East Mesa in 1979, geothermal power has increased over the years to the present 400+ MW of installed capacity in the three primary areas of Salton Sea, Heber and East Mesa. Although most in the industry are aware of the millions of kilowatt-hours annu- ally produced in this desert oasis of development, they re- main surprisingly uninformed about the Valley’s other geo- thermal industry—aquaculture.

At present, there are approximately 15 fish farming (or aquaculture) operations clustered, for the most part, around the Salton Sea. All of these farms use geothermal fluids to control the temperature of the fish culture facilities so as to produce larger fish in a shorter period of time and to permit winter production which would otherwise not be possible. In aggregate, these farms produce on the order of 10,000,000 lbs of fish per year most of which is sold into the California market. Principle species are catfish, striped bass and tilapia.

For the past several years, tilapia has been the fastest growing part of the aquaculture industry. In 1996, the total U.S. consumption of tilapia was 62,000,000 lbs. Of this, only 16,000,000 lbs (26%) was domestically produced and the bal- ance imported. The primary market for the fish on the West Coast is among the Asian-American populations in the major cities. Fish are shipped and sold live at the retail level.

RESOURCES

The geothermal fluids used by the aquaculture opera- tions are quite different from the those produced for electric power production. Table 1 presents a summary of water chem- istry for typical Imperial Valley electric power and aquacul- ture wells.

Table 1. Typical Water Chemistry - Imperial Valley Wells¹ (Youngs, 1994)

Electric Aquaculture Power Well Well Depth (ft) 2260 246 Temperature (^oF) 509 145 pH 6.1 7.8 Na 47,300 980 K 7,960 46 Ca 23,600 132 Mg 110 33 SiO₂ 435 65

AQUACULTURE IN THE IMPERIAL VALLEY - A GEOTHERMAL SUCCESS STORY -

Temperatures of the wells used by the aquaculture op- erations vary from site to site with the highest in the area to the east of the Salton Sea. Pacific Aqua Farms and the Cali- fornia Desert Fish Farm, located on Hot Mineral Spring Rd (adjacent to the area’s major hot spring resorts, see fig 2) at the foot of the Chocolate Mountains have the warmest water at approximately 165 ^oF. All of the wells in this area sustain some artesian flow though often it is not sufficient to meet the needs of the operators. In some cases, production is increased using air lifting. This method is not common in most conven- tional geothermal systems due to the corrosion resulting from the oxygen entrained in the water. In the aquaculture opera- tions, however, all of the piping is of non- metallic (mostly PVC) construction so corrosion is not as great a consideration.

Beyond this, since the fish are grown in the geothermal water, oxygen must be added later at the growout tanks.

On the west side of the Salton Sea, the wells typically produce water between 90 and 120 ^oF depending upon depth.

Shallow wells in the 200 ft range, produce water toward the lower end of these values and “deeper” wells of greater than 600 ft produce water toward the higher end. All of the wells in this area of the valley require pumps to produce the water.

Most of the larger growers have 2 to 3 wells, with a few of the smaller operations dependant upon a single well.

Due to the desert climate, high water temperatures are a major concern for the growers in the warmer portion of the year; particularly, those whose only water source is the geo- thermal fluid. Many use ponds to cool the water. A novel solution to this problem is illustrated in Figure 1. Pacific Aqua Farms uses a “cooling tower” of their own design to cool the geothermal water in the summer. Reportedly, these towers are capable of reducing the 140 ^oF water to 90 ^oF under favorable conditions. Their steel construction, however, is subject to high rates of corrosion and rebuilding is an ongoing task.

Figure 1. Cooling tower at Pacific Aquafarms.

2

LOCATIONS

Figure 2 provides a map of the area indicating the loca- tions of the individual operations. The largest concentration of operations is in the southern Riverside County region on the northwest fringe of the Salton Sea. The largest single fish farm in the valley, Kent Seafarms with a production of ap- proximately 3,000,000 lbs per year, is located in this area.

Kent grows primarily stripped bass and because these fish can- not be shipped live most of the production is shipped on ice.

Figure 2. Locations of aquaculture and geothermal power generation operations - Imperial Valley (num- bers are keyed toTable 2).

The largest single tilapia producer, Pacific Aqua Farms, as mentioned above, is located on the east side of the Sea.

Pacific produces approximately 1,000,000 lbs per year and ships most to the Los Angeles market.

Fish Producers the Valley’s largest catfish facility and one of the oldest aquaculture operations having started busi- ness in the late-1960s. It is located just east of the town of Niland. Catfish is the primary product here and annual pro- duction is in the range of 1,300,000 lbs per year. Fish Produc- ers has used a conventional pond culture (Figure 3) approach in the past. Much of the water source for this portion of the

operation is irrigation canal water. A recently constructed

“raceway” facility (Figure 4), along with two new geothermal wells, will allow them to increase production by an additional 300,000 lbs per year and also permit some development work with other species than catfish.

Figure 3. A small portion of the 70 acres of catfish ponds at Fish Producers.

Figure 4. Newly constructed “raceway” designed for a production of 300,000 lbs per year.

Table 2 provides additional information on some of the fish farms appearing in Figure 2.

Table 2. Species and Annual Production Data

No. Farm Name Species¹ Annual Prod.² Years

1 California Desert Fish Farm T 390,000 7

2 Pacific Aqua Farms T 1,000,000 12

3 Fish Producers C 1,300,000 30

4 Valley Fish Farm C 600,000 12

5 Kent Sea Farms HSB 3,000,000 12

6 Blue Aquarius C 125,000 10

7 Dashun Fisheries T 320,000 13

8 Coachella Valley Fish Farm C 450,000 unk 9 Arbia Farm ? in start up new 10 Unknown ? in start up new 11 Oceanridge T 300,000 4

12 H&T T 150,000 5

13 Hsiang Niching C,T 200,000 2

14 S S Vong T 225,000 15 15 Unknown C unknown unk

1. T = Tilapia, C = Catfish, HS = Hybrid Striped Bass 2. Estimated production in lbs per year.

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ANATOMY OF A TILAPIA FISH FARM

The following description is based on a tilapia farm pro- ducing approximately 400,000 lbs of fish per year. It is im- portant to understand that all farms are a reflection of their management and as a result, two farms growing the same spe- cies with the same annual production can be quite different in configuration. The overall layout of the farm appears in Fig- ure 5. Figures 6 through 10 provide a close up of each major aspect of the operation

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Most fish farms operate their own hatchery to maintain product quality and assure an adequate supply of fingerlings for production. The hatchery typically includes tanks for brood stock, egg collection, fry and fingerling handling. Figure 6 shows the hatchery/fingerling portion of the California Desert Fish Farm facility. Brood fish are kept in the long rectangular tanks at the upper right, eggs and fry in the small building beyond the brood tanks and various size fingerlings in the 20- and 30-ft diameter circular tanks in the foreground.

Figure 6. Hatchery area.

At a size of approximately 3 to 6 inches, the fingerlings, now referred to as juveniles, are moved to the larger tanks (Fig- ure 7) for growout. Due to the very high density of fish in the tanks, artificial aeration is necessary to maintain adequate lev- els of oxygen. Electric motor driven paddle wheel type de- vices are most common. Two paddle wheel aerators (approx 3 to 7 hp each depending on pond size) are oriented on opposite

each other. In addition to aeration, this also promotes a circu- lar flow in the tank. This flow helps to drive waste products toward the center for collection. Feed for the fish is in pellet form and size varies according to the fish size. The feed is often distributed to the pond surface using a trailer mounted hopper equipped with a blower. The circular growout tanks are of concrete and block construction.

Figure 7. 100- and 120-ft diameter growout tanks.

In a desert climate, many growers are constrained by the available supply of water. Raising fish at high density results in the need to remove waste products (solids, ammonia etc) from the recirculated water. With irrigation canal water gen- erally unavailable to most aquaculture operators, a variety of methods are used to “stretch” the geothermal water supply as far as possible. Often this involves passing the water out of the fish tanks to several large earthen ponds arranged in such a way as to cause the water to flow through them in series. These ponds remove a portion of the impurities in the water allowing some of the flow it to be recirculated.

At approximately nine months, the tilapia are large enough for sale into the market place. Market size varies ac- cording to the needs of the particular retailer at which the fish will be sold. Generally, fish in the 3/4-lb to1-lb range are con- sidered “small” and those larger than 1 1/4 lb “large.” Prices are often better for the larger fish. At this point, the fish in the large circular tanks are gathered into one corner using a large siene net. They are sorted as to size and placed in a transfer net equipped with a scale (Figure 8), for delivery to the ship- ment holding tank (Figure 9) and eventually to the transport truck.

Figure 8. Sorting and moving fish from growout to trans- fer tank.

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Figure 9. Transferring fish to delivery truck.

The fish are shipped live to the retail level in a truck equipped with a series of tanks and a liquid oxygen distribu- tion system for aeration (Figure 10). A few of the largest operations employ their own trucks and deliver directly to the markets and restaurants. In most cases, however, the grower sells to a “middle man” who owns and operates the truck and sells to the retail store or restaurant operator. Figure 11 shows a view of the transport truck in San Francisco’s Chinatown.

Figure 10. Live fish delivery truck--liquid oxygen storage tank at back.

Figure 11. Delivery truck in San Francisco’s Chinatown.

CONCLUSION

Agricultural statistics, gathered for the Coachella Val- ley for the year 1995, provide some interesting data. At that time, there were 34 individual types of crops grown on lands irrigated by the Coachella Canal. Of the approximately

$432,500,000 in gross value for these crops, approximately 3.1% was attributed to fish farm production. Interestingly, the gross revenue produced by the fish crops, per acre of land, ranks 4^th out of the 34 crops raised in the area. Only dates, bell peppers and nursery crops produced higher gross earnings per acre of land.

The substantial growth in the number of operators and annual production for aquaculture in this region is impressive.

Much of the growth has been in the production of tilapia. This reflects the national trend in the growth of aquaculture. Since 1991 the national production of tilapia has approximately qua- drupled (Aquaculture, 1998). At some point, this level of growth will begin to approach equilibrium with the market demand in certain areas. In California, where 40% of the U.S.

production is located, this may already be occurring. Prices have dropped recently, from a high of $2.30 per pound in 1995 to approximately $2.00 per pound currently. The price situa- tion was a commonly discussed topic at all of the farms visited in the course of gathering information for this article.

Based on the limited shipping distance for live fish and the finite size of the Asia-American market, it may be in the best interests of the growers to explore the establishment of some new markets for the tilapia. Tilapia burgers maybe?

Finally, the estimate of the geothermal installed capac- ity and annual energy use for the 15 famrs is 85 MWt and 1.5 trillion Btu/year, or about 500 Btu/yr/lb of fish.

ACKNOWLEDGEMENTS

I would like to thank Maria L Schwander, owner and Maria Soledad “Sol” Delgadillo, manager of the California Desert Fish Farm for their generous hospitality, guidance, great food and patience in explaining aquaculture to an engineer. I am also indebted to the owners of Pacific Aquafarms, Fish Producers, Ocean Rich Fisheries Inc, H & T Aquatics Inc and Aquafarming Tech, Inc for the time they took to show us their facilities.

REFERENCES

Aquaculture, 1998. “1997 Tilapia Situation & Outlook Report,” Vol. 24, No. 4, Asheville, NC, pp. 8-15.

Youngs, Leslie G., 1994. “Database of Low-Temperature Geothermal Springs and Wells in California,”

Division of Mines and Geology, Sacramento, CA.

KLAMATH FALLS GEOTHERMAL DISTRICT HEATING SYSTEMS

Brian Brown, P.E.

Brian Brown Engineering Ft. Klamath, OR INTRODUCTION

The city of Klamath Falls, Oregon, geothermal district heating system was constructed in 1981 to initially serve 14 government buildings with planned expansion to serve addi- tional buildings along the route. After a difficult start-up pe- riod, the system has provided reliable service since 1991. For more information on the system development, see Lienau, et al., (1989 and 1991).

The district heating system was designed for a thermal capacity of 20 million Btu/hr (5.9 MWt). At peak heating, the original buildings on the system utilized only about 20 per- cent of the system thermal capacity, and revenue from heat- ing those buildings was inadequate to sustain system opera- tion. This led the city to begin a marketing effort in 1992 to add more customers to the system (Rafferty, 1993).

Since 1992, the customer base has increased substan- tially, with the district heating system serving several addi- tional buildings and extensive areas of sidewalk snowmelt.

Figure 1 shows the service area of the district heating system.

In the winter of 1998 to 1999 the district heating system served the highest load ever, with peak loads estimated at 50 to 60 percent of the original design capacity. The system showed some strain under the load, with operational difficul- ties related to capacity, controls, and equipment failures. Sys- tem upgrade and maintenance work is scheduled for the sum- mer of 1999 to improve system capacity, control, and reliabil- ity.

BUILDING HEATING

The original and continuing primary purpose of the dis- trict heating system is to serve building space heating require- ments. The original buildings connected to the system in- cluded:

• County Museum • Fire Station • Post office • City Hall • City Hall Annex • County Library • County Courthouse • Old County Jail

• Veteran’s Memorial Building (County offices) • County Annex

The courthouse, jail, and Veteran’s buildings were all extensively damaged by an earthquake in 1993 (Lienau &

Lund, 1993). The earthquake damage caused the loss of that building space for County government use, and the loss of the heating revenue for the district heating system. These buildings were subsequently demolished and replaced.

The HVAC system controls in the County Library were upgraded in 1996, resulting in a 50% reduction in the heating costs; from about $12,000 to $6,000 per year. That was good for the County, but reduced revenue for the district heating system.

Figure 1. Map of Klamath Falls geothermal district heating system.

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New facilities added to the district heating system in1993 through 1997 included:

• Christ Lutheran Church (served off the geothermal production main)

• Balsiger Building (replacing heating from a private geothermal well)

• Eagles Club • Gospel Mission • Ross Ragland Theater • First Presbyterian Church • First Baptist Church

• Sacred Heart Catholic Church (complex of 4 buildings)

• South Valley State Bank • US Bank

• Pacific Linen (commercial laundry) New in 1998:

• Klamath County Government Center building. This building is a renovation of the old County Annex building with a significant new addition. The construction included a complete new HVAC system.

New and under construction for 1999:

• Howard’s Body Shop

• Klamath County Courthouse. This is a new replacement for the earthquake damaged and demolished original courthouse.

• Addition to the Ross Ragland Theater. This addition will increase the heated floor space from about 12,000 ft² to about 22,000 ft² The total heating load is expected to remain about the same due to added insulation and improved heating system controls in the original building.

As of the winter of 1998 - 1999, the estimated design peak load for the buildings on the district heating system is about 8 x10⁶ Btu/hr (2.3 MWt).

DESIGN OF THE COUNTY GOVERMENT CENTER BUILDING HEATING SYSTEM

The new county buildings are the first on the geothermal district heating system with efficient use of the system incor- porated in the original design. Important features of the heat- ing system design include:

• Heating coils are selected for low flow and high water-side temperature drop (delta-T).

• Heating water control valves are mostly 2-way valves, resulting in a variable heating water flow and a high heating water system delta-T.

• Heating water pumps are controlled by adjustable frequency drives, minimizing pumping energy use and accommodating the variable heating water flow.

• The building heating water supply temperature is aggressively reset to a lower temperature at higher outside air temperatures and lighter building heating demand.

• Lower temperature loads, such as the sidewalk snowmelt system, are served from the heating water return, increasing overall delta-T.

• The control valve on the district heating water supply is closely controlled to meet building heating loads while minimizing the flow and maximizing the delta-T.

Figure 2. Klamath County Government Center Building.

The beneficial result of these design features is the main- tenance of high system delta-T, meeting the heating demand with the minimum flow from the district heating system. The high delta-T benefits the geothermal district heating system all the way back to the production wells. Operation of the system at high delta-T reduces pumping costs, improves performance of heat exchangers, and increases the energy delivery capacity of the system.

Figure 3. Government Center district heating heat ex- changer.

The city does not guarantee uninterrupted service, as is the case with other utilities, from the district heating system;

consequently the county building heating system includes a back-up boiler. The controls in the County Government Cen- ter building monitor the status of the district heating system and automatically operate the back-up boiler to supplement

the heat available from the district heating system or to pro- vide complete back-up heating. The controls compare the sup- ply temperature available from the district heating system with the set-point temperature for the building heating water sys- tem. If the district heating system is colder than the required building heating water temperature, the district heating con- trol valve is closed to prevent heat loss from the building sys- tem. Once the district heating system is returned to service, the controls initiate an automatic warm-up sequence to purge the cold water from the system piping. After the district heat- ing supply temperature returns to normal and is adequate to meet the building heating demand, the boiler shuts off auto- matically.

Figure 4. Klamath County Government Center district heating flow control valve. Good flow control is vital for efficient operation.

Over the 1998 to 1999 heating season, the district heat- ing system experienced more than the ususal number of ser- vice interruptions from power outages, control problems, and production well problems. In all cases, the boiler controls pro- vided automatic, uninterrupted heat to the building, while mini- mizing boiler run time.

Figure 5. Government Center heating water, boiler, and snowmelt controls.

The County Government Center building includes about 37,000 ft² of conditioned floor space and about 10,000 ft² of heated sidewalks. The peak heating design load for the build- ing and sidewalks was estimated to be 2.4 x 10⁶ Btu/hr (0.7

MWt), requiring a peak flow rate from the district heating sys- tem of 120 gpm at 40°F delta-T, based on a 180°F supply tem- perature from the district heating system and 140°F return tem- perature. The peak measured load in February, 1999 (after installation and setup of the meter) was 1.3 x 10⁶ Btu/hr (0.38 MWt) with a peak flow of 50 gpm. Annual energy consump- tion is estimated to be about 1.8 x 10⁹ Btu (520 MWht).

Figure 6. Government Center snowmelt heat exchanger.

Performance of the building heating system has been excellent, exceeding design expectations. Typical district heat- ing return water temperature is 110°F when the snowmelt sys- tem is operating in the IDLING mode; and 120°F when the snowmelt system is off or operating in the higher temperature MELT mode. This return temperature is well below the de- sign 140°F, and reflects the capability of the heating system to operate in a higher than design delta-T. The performance of the system can be attributed to a combination of system de- sign, conservative heat exchanger sizing, and careful design and programming of the Alerton DDC control system.

trict heating system through a building heating system or di- rectly from the district heating mains. These installations in- clude the County Government Center building, the Basin Tran- sit bus transfer station, Sacred Heart Catholic Church, City Hall, City Hall Annex, South Valley Bank, and KOTI. The installed area of these systems is about 19,000 ft². About 15,000 ft² of additional private snowmelt system area is anticipated for 1999.

SIDEWALK SNOWMELT

Geothermally heated sidewalks and crosswalks have been incorporated into a downtown redevelopment project along Main Street, starting with the 800 block in 1995. (Brown, 1995). That snowmelt system has been extended to cover nine blocks of sidewalks and crosswalks, from 2^nd Street to 11^th Street. The heated sidewalk and crosswalk area currently served by the city snowmelt system is about 51,000 ft². An- ticipated additions to the city system in 1999 will bring the total area to about 60,000 ft².

Several snowmelt systems have also been installed sepa- rate from the main City snowmelt system, served from the dis-

8

Figure 7. Klamath Falls snowmelt system control panel with author Brian Brown, P.E., consulting engineer.

The sidewalks are heated by circulation of a heated anti- freeze solution through a network of polyethylene tubes im- bedded in the sidewalks or in a sand or slurry base under the sidewalks. The solution is heated through a heat exchanger from the building heating water system or the district heating water. Where feasible, the heat is extracted from the return water side of the heating system to increase the overall district heating system delta-T.

Figure 8. Snowmelt tubing in slurry backfill under side- walks.

Most of the snowmelt systems are designed for a heat output of 60 to 80 Btu/h·ft² of heated sidewalk. That design heat output is adequate for convenience snow melting under most conditions in Klamath Falls. It will not keep the side- walk above freezing in extremely cold conditions, or keep up with high snowfall rates. Figure 9 shows the slush accumula- tion after a heavy snowfall this past winter. Figures 10 and 11 shows a section of sidewalk after the system had a chance to catch up. The sidewalk beyond does not yet have the snow- melt system installed. The trees are protected with styrofoam insulation to keep them from budding in the winter during sys- tem operation.

Figure 9. Slush accumulation after a heavy snowfall.

Figure 10. Clear sidewalk after snowfall. Tree well is protected from heat by insulation. Sidewalk beyond is not heated.

Figure 11. Basin Transit transfer station snowmelt.

The snowmelt systems have become a significant por- tion of the total district heating system load, with an estimated design peak load of about 4 x10⁶ Btu/hr (1.2 MWt).

SYSTEM GROWTH AND CAPACITY

The peak load under normal design winter conditions for currently connected users is estimated to be about 60% of design system capacity, or 12 x10⁶ Btu/h (3.5 MWt). The peak

load is not precisely known, since the system has not had flow and energy monitoring. With improved controls and monitor- ing on-line for the ‘99-‘00 heating season we will be better able to track system operation and project system reserve ca- pacity.

Without system flow and energy instrumentation, evalu- ation of system load and reserve capacity has been based on general observations of system performance. Operation in the

‘95-‘96 heating season indicated pump flow capacity concerns in the district heating closed loop, primarily due to poorly con- trolled flow at many of the users and the resulting low system delta-T. Improved flow control at three of the larger users improved that situation, and there were no capacity problems in the ‘96-‘97 and ‘97-‘98 heating seasons.

In the ‘98-‘99 heating season the circulation pump still showed adequate capacity, maintaining more than 15 psi pres- sure differential between the district heating supply and return at the far end of the system. The system delta-T remained lower than design, with a typical delta-T of about 13°F and maximum delta-T of about 24°F; compared to the design delta- T of 40°F. This indicates that more work on flow control is necessary.

The system was designed to operate both production wells at design capacity, but that has never been necessary.

Typically the lower, cooler (206°F) well is operated in the mild seasons and the hotter (226°F) upper well is used in the colder part of the winter. In December, 1998 the temperature dropped to -10°F, the coldest it has been for several years. Under those conditions, the upper well was unable to maintain the desired district heating supply temperature of 180°F. That may be partially due to fouling on the heat exchangers, but it also indi- cates a need to either increase the pumping capacity of the upper well, or begin operating both wells to meet the peak heating loads.

OPERATION AND IMPROVEMENTS

The district heating system has run close to nonstop since 1993, with short or partial shutdowns for system connections or maintenance. Extensive system maintenance is planned during a system shutdown in the summer of 1999. Planned work includes:

• Replacement of all critical isolation valves to facilitate future maintenance

• Installation of a second large circulation pump on the closed-loop system with an adjustable frequency speed control

• Improved control of flow to connected buildings • Rehabilitation of the upper geothermal well pumps

and replacement of the Nelson fluid drives with a larger motor and adjustable frequency speed control. Pump capacity will be increased 60%, from 500 gpm to 800 gpm.

• Cleaning of the main heat exchangers and addition of about 50% more plates

• Replacement of the system controls with digital programmable logic controller (PLC) based

controls, with radio telemetry between the heat exchanger building, the remote pump stations, and the system manager’s office

• Installation of new magnetic flow meters for geothermal and closed loop flow and energy measurement

• Cleaning and painting exposed pipe and fittings in tunnels and vaults

• Improved ventilation of expansion joint vaults and the production pipeline tunnel to reduce moisture accumulation and corrosion

• Maintenance of the pipeline cathodic protection systems

The planned system maintenance and improvements will improve the reliability and capacity of the district heating sys- tem to meet the existing and planned heating load. The im- proved flow control and adjustable speed pumping are also anticipated to reduce the electrical cost of operating the sys- tem by about 75 percent.

CONCLUSIONS

The city of Klamath Falls geothermal district heating system has experienced considerable growth in the past few years. Additional expansion is scheduled for 1999, and there is considerable additional interest in hooking onto the system.

System maintenance and control system improvements sched- uled for 1999 will make the system more reliable and less ex- pensive to operate. This combination should help the district heating system make the transition from a subsidized experi- ment in renewable energy to a fully self-sustaining utility.

REFERENCES

Brown, B., 1995. “Klamath Falls Downtown Redevelop- ment Geothermal Sidewalk Snowmelt,” Geo-Heat Center Quarterly Bulletin, Vol. 16, No. 4., p. 23- 26.

Lineau, P.; Culver, G. and J. Lund, 1989. “Klamath Falls Geothermal Field, Oregon, Case History of Assess- ment, Development and Utilization.” Presented at Geothermal Resources Council 1989 Annual Meeting, Santa Rosa, CA.

Lineau, P. and K. Rafferty, 1991. “Geothermal District Heating System: City of Klamath Falls, ” Geo-Heat Center Quarterly Bulletin, Vol. 13, No. 4., p. 8- 20.

Lienau, P. and J. Lund, 1993. “Groundwater Anomalies Associated with the Klamath Basin Earthquakes of September 20-24, 1993,” Geo-Heat Center Quar- terly Bulletin, Vol. 15, No. 2, pp. 17-19.

Rafferty, K., 1993. “Marketing the Klamath Falls Geother- mal District Heating System,” Geo-Heat Center Quarterly Bulletin, Vol. 15, No. 1., p. 4-6.

10

THE OREGON INSTITUTE OF TECHNOLOGY

GEOTHERMAL HEATING SYSTEM - THEN AND NOW

Tonya L. Boyd Geo-Heat Center

INTRODUCTION

Oregon Institute of Technology (OIT) is located on a hill, which gently slopes from the east to the west, in the north- east part of Klamath Falls. The campus has been using geo- thermal water, for its heating and domestic hot water needs, since it was relocated to this location in 1964. It has been in continuous operation for 35 years and now heats 11 buildings (~600,000 ft² / 55,700 m²). It is the oldest of the modern geo- thermal district-heating systems, and due to the lack of expe- rience with the design of large systems in the early-1960s, it has experienced some difficulties through the years. These difficulties have been resolved and the experience has pro- vided a substantial body of information concerning the appli- cability of various materials and designs for low-temperature use. The original system, which provided heating and do- mestic hot water for the five original buildings, consisted of constant-speed, water-lubricated lineshaft pumps located in well pits. The pumps were run manually according to the level in the storage tank. The distribution system consisted of direct-buried Schedule 40 carbon steel piping which was field insulated with “Foamglas” type insulation and covered with a

“mastic” vapor barrier. The geothermal water was used di-

rectly in the buildings’ mechanical heating systems; then, the effluent was disposed of to the surface through the storm drain- age system than eventually emptied into Upper Klamath Lake.

Cooling for the campus was accomplished by an electric-pow- ered chiller.

Figure 1 shows a general layout of the OIT system as it is today. Geothermal water for the system is produced from three wells at a temperature of 192^oF (89^oC), which are lo- cated in the southeast corner of the campus. The wells are from 1300-1800 ft (400-550 m) in depth. The water is pumped individually from each well (total flow of all the wells is 980 gpm/62 L/s). The water is then collected in a 4000-gal (15- m³) settling tank in the Heat Exchanger building before it is delivered to each building via gravity through the distribution system according to demand on the system. The settling tank (Figure 2) provides the necessary head for the gravity flow system and allows the fines from pumping to settle out of the water. The heat exchanger building also housed a fuel-oil boiler from the old campus as a backup; but due to lack of use, it was dismantled several years ago. The geothermal sys- tem saves approximately 11,000 bbl (1650 tonnes) of oil or

$225,000 each year.

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Figure 1. General layout of the OIT geothermal system.

Figure 2. The 4000-gal (15-m³) settling tank located in the Heat Exchanger building.

THE PROBLEMS ENCOUNTERED AND THE SOLUTIONS

Pumps

After approximately six years of operation, a major re- design of the pumping system was carried out. The original constant-speed, water-lubricated lineshaft pumps, were virtu- ally the same as cold-water irrigation pumps and were located in wellhead pits. Placing the pumps in the pits didn’t allow for air circulation which lead to overheating and condensation prob- lems. The earlier pumps also didn’t provide for the expansion of the piping in the well; therefore, the lineshaft had to be pre- heated to produce sufficient clearance before the pump was started. This meant one pump had to be kept running all the time. The pumps also experienced other failures. The original bronze impellers were attached to the shaft with collets and the failures occurred when the impellers detached from the shaft. The most serious problem was related to the failure of the shaft bearings. A number of bearing types were used, but none proved to have acceptable lifetimes. It was reported that the bronze bearings “burned up,” and the rubber and teflon bearings “swelled.”

Figure 3. One of the pumps and variable-speed controllers with the housing removed.

During the redesign of the pumps, extra lateral bowls were installed to eliminate the need for shaft preheating. The impellers were attached with both keys and collets. At this point, it was also decided to isolate the bearings from the geo- thermal water using an oil-lubricated enclosed lineshaft arrange- ment. To help with the overheating and condensation prob- lems, it was decided to raise the pumps to ground level and enclosed them in housing (Rafferty, 1989). Figure 3 shows one of the pumps with the housing removed.

Distribution System

The original distribution system consisted of direct-bur- ied Schedule 40 carbon steel piping, field insulated with

“Foamglas” insulation and covered with a “mastic” vapor bar- rier. This piping system suffered internal and exterior corro- sion. The external corrosion was due to the expansion and movement of piping which caused the mastic vapor barrier to break. This failure allowed groundwater and salt water from deicing to come in contact with the piping, resulting in the external corrosion. After 14 years of service, an examination of the piping revealed an internal buildup of scale. The scale consisted of mainly silica and iron oxide with the iron oxide being closest to the pipe. In many places, the piping wall thick- ness was reduced to one-third of its original thickness. The fact that the main settling tank was vented to the atmosphere permitted oxygen to enter the system, which promoted the in- ternal corrosion. The storm sewer system used for disposal of the effluent also encountered failures. This part of the system consisted of cast iron and carbon steel piping located in the buildings, galvanized culverts from the buildings to the main line, and concrete culverts in the main line. All of the failures occurred in sections with galvanized culverts. This could have been a result of dezincification (galvanized coating removed) and eventually corrosion of the unprotected steel surface (Rafferty, 1989).

In response to the piping failures, it was decided to con- struct a new distribution system and a dedicated collection sys- tem along with the construction of utility tunnels to connect all the buildings. The design of the tunnel (6 ft x 6 ft / 2 m x 2 m) provides access for maintenance personnel and space for other campus utilities. During construction the concrete was formed and poured in place to allow for forming around building foun- dations and utility pipes running at an angle to centerline (Fig- ure 4). The floor of the tunnel is 8 in. (20 cm) thick and the sides 6 in. (20 cm) thick. The pipes are held to the side with pipe clamps and Unistrut hangers. In some cases, the tunnel also serves as a sidewalk; thus, snow-melting is enhanced due to the heat loss through the system. The cost of constructing the tunnel system (including excavation and backfill) was ex- tremely high at about $160/lf ($525/m), which didn’t include the cost of the piping. The cost of the piping varied from $15/

ft ($50/m) for 6-in. (15-cm) diameter to $22/ft ($72/m) for 8- in. (20-cm) diameter pipe. When new extensions to the tunnel system were added, a 6-ft (2-m) diameter corrugated galva- nized steel culvert was used instead of concrete. Its estimated cost was only 25 percent of the cost for concrete tunnels (Lund and Lienau, 1980).

12

Figure 4. View of the tunnel under construction.

Heat Exchangers

In the original design, the geothermal water was used directly in each of the building mechanical systems. This “once through” approach eliminated the need for circulation pumps in the buildings. The direct use of the geothermal fluids caused problems due to the corrosive nature of the water. The origi- nal chemical analysis of the water failed to consider the effect of H2S (hydrogen sulfide) and NH4 (ammonia) on the copper and copper alloys used in the mechanical system. There were a number of different types of failures identified that occurred as a result of using the water directly. The most important ones are listed below:

• Failure of the 50/50 tin/lead solder connections, • Rapid failure of 1% silver solder,

• Wall thinning and perforation of copper tubing was a common occurrence,

• Control valve failures where plug (brass) was crimped to the stem (stainless steel). The threaded ones experienced no problems, and

• Control valve problems associated with packing leakage.

thermal water at 100 gpm (6.3 L/s) and the building water at 54 gpm (3.4 L/s). The building water is then circulated through finned-tube pipe heat convectors located along the outside walls of the building. The second loop provides 30,000 Btu/hr (30 MJ/hr) using geothermal water at 25 gpm (1.4 L/s) and build- ing water at 12 gpm (0.65 L/s). The building water is then circulated through reheat coils, which provides heating through a forced-air system for the interior of the building (Lund and Lienau, 1980).

Figure 5. The College Union heat exchanger.

Fluid Disposal

Discharge to the surface was the original approach for disposal of the geothermal effluent. Although surface discharge is the simplest and least expensive option, there were several possible potential problems. The discharge temperature of the waste effluent was still quite high (135^oF/57^oC-winter and 170^oF/77^oC-summer) when it was delivered to the ditch. This method presented a safety hazard. A local city ordinance was passed which banned surface disposal and required all opera- tions in the city to establish an injection program by 1990.

OIT now has two injection wells to compile with the ordinance.

The first injection well was drilled using standard mud-rotary techniques, and the second well used a combination of meth- ods with air drilling in the injection zone. During the initial pumping test of the first injection well, the maximum obtain- able pumping rate was only 200 gpm (12.6 L/s). It was be- lieved that a considerable amount of drilling mud had invaded fractures in the primary production zones. The well was acidized (13% hydrochloric acid, 3% hydrofluoric acid) twice;

this increased the capacity from 200 to 400 gpm (12.6 to 25.2 L/s). Analysis of test data indicated that the aquifer was still clogged with drilling mud at about 25 times the effective ra- dius of the well. The maximum injection rate was estimated to be 600 gpm (37.8 L/s). The second injection well easily handles 1,000 gpm (63 L/s) and could possibly accept as much as 2,500 gpm (158 L/s) at 50 psi (3.4 bar) injection pressure is allowed at the wellhead. This well is being used as the primary injec- tion well. Experience with these injection well suggest that air drilling can be quite beneficial in terms of subsequent well performance (Lienau, 1989).

To address these problems, it was decided to isolate the geothermal water from the building heating systems using plate heat exchangers. Based on an analysis study, heat exchangers with 316 stainless steel plates with Buna-N gaskets were se- lected. The stainless steel heat exchanger used to heat the cam- pus swimming pool failed within the first three years of opera- tion. This failure occurred on the pool’s water side of the heat exchanger, probably as a result of the high chorine content.

The pool’s heat exchanger was eventually replaced with tita- nium plates (Rafferty, 1989).

Some of the building systems utilize two loops through the heat exchanger. The College Union building plate heat exchanger, shown in Figure 5, utilizes two loops. The first loop provides 1,350,000 Btu/hr (1,350 MJ/hr) using the geo-

NEW ADDITIONS TO THE SYSTEM Snowmelt System

The newest additions to the OIT system are two sections of sidewalk snowmelting located by the Residence Hall. This brings the total amount of sidewalk snowmelting to 2,300 ft² (214 m³). The other sections include the wheelchair ramp in front of South Hall and a couple of stairwells (Figure 6) lead- ing to upper sections of the campus. All systems utilize 5/8-in.

(1.6 cm) diameter cross-linked polyethylene tubing (PEX). The wheelchair ramp has four loops with the tubing spaced 10 in.

(25 cm) apart. The stairs has three loops with the tubing tied to the existing stairs. Figure 7 shows the placement of tubing on a stairwell before the form work was added. The systems should be able to maintain a slab surface temperature of 38^oF (3^oC) at -5^oF (-21^oC) air temperature and 10 mph (16 km/h) wind when the entering 50/50 propylene glycol/water temperature is144^oF (62^oC). Each stair section uses a brazed-plate heat exchanger to isolate the glycol-filled snowmelt loop. The new snowmelt systems installed have slab temperature sensors which will activate the system when the outside air is 30^oF (- 1^oC)(Geothermal Pipeline, 1994).

Figure 6. One of the stairwell leading to the College Union.

Figure 7. Placement of the snowmelt tubing before the formwork was added.

Purvine Hall

Purvine Hall utilizes the geothermal waste effluent from the rest of the campus for its space heating and domestic hot water heating. The temperature of the effluent as it enters the building is around 155^oF (68^oC) and leaves at a temperature of around 130^oF (54^oC). The main components of heating sys- tem include a 4,000-gal (15-m³) storage tank, circulation pumps and heat exchangers. On the building heating side, space heat- ing is accomplished by 54 variable air volume terminals equipped with hot water coils (Fields, 1989).

Absorption Chiller

A lithium-bromide absorption chiller was installed in 1980. It has a nominal 312 ton (1095 kW) capacity; but due to the low temperature of the water entering the system (192^oF/

89^oC), it only produces 150 tons (526 kW) of cooling. The chiller requires 685 gpm (37.8 L/s) of geothermal fluid and only takes a 20^oF (11^oC) delta T out of the water. Recorded installation cost for the chiller was $171,300. The geothermal chiller supplies a base cooling load to five campus buildings or 277,300 ft² (25,800 m²). The original electrical centrifugal chiller is now being used for peaking above the capacity of the absorption chiller. Since the geothermal water is used directly in the generator tubes of the absorption chiller there is a poten- tial for corrosion to occur. The generator tubes are constructed of 90-10 cupro-nickel; but, no failures have occurred in the past 18 years (Lund and Lienau, 1980). Due to the low effi- ciency and high water usage, the absorption chiller will be re- placed this summer with a centrifugal water chiller.

REFERENCES

Fields, Paula G., 1989. “Purvine Hall Geothermal Heating System,” Geo-Heat Center Quarterly Bulletin, Vol.

11, No. 4, pp. 16-17.

Geothermal Pipeline, 1994. “Geothermal Wheelchair Ramp Installed at OIT,” Geo-Heat Center Quarterly Bulletin, Vol. 16, No. 1, pp. 24-25.

Lienau, Paul, 1989. “OIT Injection Well,” Geo-Heat Center Quarterly Bulletin, Vol. 11, No. 4, pp. 9-11.

Lund, John W. and Paul J. Lienau, 1980. “New Geothermal Construction on the OIT Campus,” Geo-Heat Center Quarterly Bulletin, Vol.5, No. 3, pp. 21-23.

Rafferty, K. 1989. “A Materials and Equipment Review of Selected U.S. Geothermal District Heating Sys- tems.” Geo-Heat Center, Klamath Falls, OR.

USDOE Contract # DE-FG07-87-ID 12693.

Gibson, Raymond, 1999. Personal communication. Oregon Institute of Technology.

Masl, Bruce, 1999. Personal communication. Oregon Institute of Technology.

14

RECONSTRUCTION OF A PAVEMENT GEOTHERMAL DEICING SYSTEM

John W. Lund

Geo-Heat Center HISTORICAL BACKGROUND

In 1948, US 97 in Klamath Falls, Oregon was routed over Esplanade Street to Main Street and through the down- town area. In order to widen the bridge across the U.S. Bu- reau of Reclamation “A” Canal and to have the road cross under the Southern Pacific Railroad main north-south line, a new bridge and roadway were constructed at the beginning of this urban route. Because the approach and stop where this roadway intersected Alameda Ave (now Hwy 50 - Eastside Bypass) caused problems with traffic getting traction in the winter on an adverse 8% grade, a geothermal experiment in pavement de-icing was incorporated into the project.

A grid system within the pavement was connected to a nearby geothermal well using a downhole heat exchanger (DHE). The 419-foot well provided heat to a 50-50 ethylene glycol-water solution that ran through the grid system at about 50 gpm. This energy could provide a relatively snow free pavement at an outside temperature of -10^oF and snowfall up to 3 inches per hour, at a heat requirement of 41 Btu/hr/ft². The grid was composed of 3/4-inch diameter iron pipes place 3 inches below the surface on 18-inch centers. The pipes were field wrapped in what appears to be an asphalt impregnated material to protect them from external corrosion.

The temperature drop in the grid was approximately 30 to 35^oF with the supply temperature varying from 100 to 130^oF and the return temperature 70 to 10^oF. This was estimated to supply a maximum of 3.5 x 10⁵ Btu/hr to the grid at the origi- nal artesian flow of 20 gpm, and 9.0 x 10⁵ Btu/hr at the pumped rate of 50 gpm. ( Lund, 1976).

REHABILITATION OF THE ODOT WELL

Over time, the well temperature drop from 143 to 98^oF at the surface. In order to maintain the downhole heat ex- changer temperature, a pump was added to the well which pumped and discharged approximately 10 gpm of geothermal water into the storm system to increase the heat flow. How- ever, in 1985, the City of Klamath Falls adopted the Geother- mal Resource Act which required all sewer or surface dis- charge from geothermal wells be eliminated. Since discharge from the well to the sewer was not longer permitted, the well was modified in 1992 by deepening it to about 1000 feet and casing it to 900 feet. The greater depth increased the tem- perature of the entering water. In addition, the Schedule 40 black iron pipe with malleable couplings was changed to Schedule 80 steel in the top leg of the DHE, the U-trap at the bottom constructed of Schedule 80, and the balance of the DHE fitted with Schedule 40 pipe. The DHE was extended to 900 feet to provide additional energy and to be exposed to more of the hotter water. Several section of Roscoe Moss standard louvre-type screen was installed and a lower seal

added. The total cost of the modifications was about $115,000.

The net result was that the “new” well produced approximately the same temperature in the grid loop as the “old” well with the pump discharging geothermal fluid to the sewer (Thurston, et al., 1995).

RECONSTRUCTION OF THE BRIDGE AND PAVE- MENT SURFACE

At the time of the well rehabilitation, a study by the Bridge Section of the Oregon Department of Transportation (ODOT) recommended that the roadway and the geothermal heat distribution system be reconstructed in six years. This recommendation was based upon the age and condition of the existing portland cement concrete (PCC) surface, leaks in the heating grid, and the annual maintenance costs. The wrought iron tubing cast into the bridge deck and pavement leaked so badly from corrosion that the deicing system was approach- ing complete failure. Annual maintenance costs were estimated at $9,000 to $10,000 a year, increasing approximately $2,000 a year due to the deterioration (Thurston, et al., 1995).

Figure 1. Original iron header pipe showing external corrosion at a break on the protective mastic covering.

In the fall of 1998, a contract was issued for the recon- struction of the bridge deck and highway pavement along with replacing the grid heating system. In addition to replacing the surface and tubing, the circulating pump was upgraded and electronic monitoring and control system added. Except for landscaping, the project was completed by early December, 1998 and is now in operation and is proving effective at keep- ing the bridge free of ice and snow. The deicing portion of the pavement is 442.5 feet long and 53.5 feet wide with about a 160-foot by 10-foot section removed for the piers support- ing the railroad bridge and for landscaping.

Figure 2. Overall project design.

The top portion of the bridge deck was hydro-blasted to remove six to seven inches of the PCC pavement. Holes were drilled through the deck to the header pipes hung underneath.

Wirsbo 5/8-inch ID hePEX (a cross-linked polyethylene) tub- ing was placed in a double overlap pattern at 14-inch on center spacing across the deck on top of a mat of reinforcing steel.

These tubes were then covered with a fresh layer of PCC. An RTD temperature sensor was placed in the bridge deck and an ambient sensor on an adjacent power pole.

The pavement section from the edge of the bridge deck, through the railroad underpass and to a point opposite the well building was completely removed. The subgrade was exca- vated to make room for about six inches of gravel base. Forms were installed and a steel mesh placed on top of the compacted subgrade within the forms. Geothermal black iron header pipes (supply and return) varying from 1.25 to 2.5 inches in diam- eter were placed outside the forms along the north side of the roadway. These header pipe had a brass manifold placed at about 40-foot intervals, to allow for four supply and return PEX pipes to be attached. The 3/4-inch PEX grid system pipes where then attached by wire to the reinforcing steel at 14-inch on center transverse to the roadway. Under the railroad under- pass, the tubing was placed longitudinally at about 16 inches on center, due to the narrowness of the pavement at this point.

Concrete (PCC) was then placed which provided for a cover over the pipes of about 3 inches. The header pipes, were insu- lated with about one inch of Armstrong Armflex pipe insula-

tion and then covered with an aluminum foil vapor barrier.

The manifolds were placed in concrete boxes for easy access for future maintenance. The header pipes, provided with two expansion loops and a concrete anchor, were covered with earth and then had concrete slope paving placed on top for protection.

Figure 3. A four-loop section ready for concrete place- ment.

16

Figure 4. Attaching the loop pipes to the manifold.

Figure 5. Details of the manifold box.

Figure 6. Iron header pipe with insulation.

Each manifold had four supply and return pipes that made four loops for a total length of about 430 feet each. Two loops were staggered on top of each other to balance the temperature loss in each loop - i.e. the hot end of one was placed adjacent to the cold end of the other, since there could be as much as 35^oF temperature drop in each loop. The PEX grid pipe is designed for 180^oF at 100 psi and 200^oF at 80 psi according to ASTM specification F 876. The pipes are filled with an ethyl- ene glycol mixture through an air vent at the high point on the bridge deck.

Figure 7. Details of a four-loop section with manifold.

Figure 8. Longitudinal loops under the railroad bridge.

The entire cost of the reconstruction project was approxi- mately $430,000 and the estimated annual maintenance cost will be $500 and the operating cost (for the circulating pump)

$3,000. The heated bridge deck covers 22,000 square feet and is designed for a heat output of 50 Btu/sq.ft/hr. This is suppose to keep the deck clear during heavy snowfall down to -10^oF.

During the first days of operation after a snowfall, the DHE supply temperature was 100^oF and the return temperature 76^oF for a delta-T of 24^oF. Once the ground and concrete tempera- tures reach equilibrium, it is expected that the supply and re- turn temperatures will increase by as much as 30^oF. The reno- vated deicing system appears to be operating effectively, based on substantial snowfalls in January and February, 1999.

Figure 10. January snowfall looking east

Figure 11. January snowfall looking up the 8% grade to the traffic signal and bridge deck.

ACKNOWLEDGEMENTS

Special thanks to the Oregon Department of Transporta- tion for providing plans and information, especially to Ms.

Meredith E. Mercer, project designer; Jason Armstrong, the inspector; and to Powley Plumbing, Inc. of Klamath Falls, the geothermal system installers, for answering many of author’s questions.

REFERENCES

Lund, John W., 1976. “Geothermal De-Icing of a Highway Pavement.” Geo-Heat Center Quarterly Bulletin, January, Vol. 1, No. 3, pp. 7-9.

Lund, John W., 1976. “Geothermal De-Iceing of a Pave- ment - Part II.” Geo-Heat Center Quarterly Bulletin, April, Vol. 1, No. 4, p. 7.

Thurston, Rachel, E.; Culver, Gene and John W. Lund, 1995.

“Pavement Snow Melting in Klamath Falls - Re- habilitation of the ODOT Well.” Geo-Heat Center Quarterly Bulletin, February, Vol. 16, No. 2, pp. 23-28.

Figure 9. End of project and pump house in back- ground.

18

LOVE THREE HOT SPRINGS OUT OF THE THOUSANDS - HOT CREEK, FIELDS AND ASH -

Bill Kaysing King City, CA HOT CREEK

This has to be a divine design. An icy stream de- scending from the High Sierras meets a stream-bed steam vent only a short distance from Highway US 395 above Bishop, California.

What this produces is a delightful and varied hot springs bath . You have your choice of toasting your toes by probing the stones of the creek bottom or having the feeling of being in an ice-cube-filled cocktail shaker. And you can enjoy ev- ery temperature in between! There’s a thrill in knowing that you are cavorting in a “crack in the cosmic egg,” dancing in a geothermal miracle.

I should mention that I have not been there in years and things could have changed; but, I hope not. This is one of our Great Spirit’s finest aquatic playgrounds.

Hot Creek Springs FIELDS

I call it this because it is close to a tiny village with that name. To find it, just take the dirt road north from Fields in far eastern Oregon and watch for a small lake to your right.

On cold days, the vapors rising from the surface will tag it.

Just imagine a lake of about an acre in size full of water around 100^oF. No one in sight. The mysterious Steen’s mountains to the west and not a sound. This has to be either an energy votex or a metaphysical feng shui or simply a super wonder- ful geothermal spring.

I recall swimming to the center of the lake and remem- bering that someone in Fields said it was 7,000 feet deep. What a mystical and magical concept.... to be suspended by warm water over a deep chasm in Mother Earth. My beloved and

recently departed soul mate and fellow hot springs lover, Ruth, loved it. And I will always remember how she was sunbath- ing on the crusty beach when a small snake slithered under her neck. I was shaken by the thought it could be venomous;

but, Ruth was in a state of hot springs euphoria along with her usual courage and elan, and she never even quivered.

Fields Springs

ASHIf you drive northeast from Vegas on I15, you will in- tersect the Pan-American Highway US 93. Turn north and drive between the towering Sheep Range and the charming Meadow Valley Wash for about 80 miles. You’ll know you’re at Ash Springs when you see a totally gigantic cottonwood on your left along with a small store. Turn right into a dirt road for less than a block and you should see a small concrete- lined pool. Toss your clothes off if no one is there and leap in.

No shock, just bliss as the water is just about body tempera- ture. It pours out of a sub-surface pipe, keeps the pool spar- kling clean and then flows down to a warm water lake of about two acres. The pool is on BLM land and open to the public all year. The lake is privately owned and you should make in- quiry before using it.

I once spent an entire week at Ash, bathing in that luxu- rious, velvet-textured water amidst a forest of willows and cottonwoods, roaming through the nearby desert hills and enjoying campfire meals in the evening. Experiences like that convinced me that being a hot springs gypsy was quite possi- bly the highest and best use of my life or anyone’s life for that matter.

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EPILOG

Hot springs, how I love them and how fortunate to have visited so many in the last four decades. If readers have ques- tions, I’ll be happy to try to answer them. Bill Kaysing, PO 1095, King City, CA 93930 [only 20 miles from Paraiso (Para- dise Hot Springs)].

Editor’s Note: Bill Kaysing - author, inventor, sailor and vagabond - has written a classic book on “Great Hot Springs of the West” covering 1,700 known hot springs that flow in the 11 western states.

We have since learned from the U.S. Fish and Wildlife Service that there is a species of fish in Ash Springs (Crenicthys baileyi baileyi), that is listed federally by the Endangered Spe- cies Act.

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